The following table summarizes information relating to our long-term debt, which we collectively refer to as our Senior Notes (in millions, except interest rates):

		July 31, 2020			April 24, 2020
	Effective Interest Rate	Amount			Amount
3.375% Senior Notes Due June 2021	3.54%	$	—		$	500
3.25% Senior Notes Due December 2022	3.43%		250			250
3.30% Senior Notes Due September 2024	3.42%		400			400
1.875% Senior Notes Due June 2025	2.03%		750			—
2.375% Senior Notes Due June 2027	2.51%		550			—
2.70% Senior Notes Due June 2030	2.81%		700			—
Total principal amount			2,650			1,150
Unamortized discount and issuance costs			(20	)		(4	)
Total long-term debt		$	2,630		$	1,146

In June 2020, we issued $750 million aggregate principal amount of 1.875% Senior Notes due 2025, $550 million aggregate principal amount of 2.375% Senior Notes due 2027 and $700 million aggregate principal amount of 2.70% Senior Notes due 2030, for which we received total proceeds of approximately $2.0 billion, net of discount and issuance costs. Interest on these Senior Notes is payable semi-annually in June and December. On July 27, 2020, we extinguished our 3.375% Senior Notes due June 2021 for an aggregate cash redemption price of $513 million, plus accrued and unpaid interest. As part of the debt extinguishment, we recognized a loss of $14 million, which includes a cash redemption premium of $13 million and the write-off of unamortized discount and issuance costs totaling $1 million. The loss on extinguishment of debt is included in other income (expense), net in our Condensed Consolidated Statement of Operations for the three months ended July 31, 2020.

Our 3.30% Senior Notes, with a principal amount of $400 million, were issued in September 2017 with interest paid semi-annually in March and September. Our 3.25% Senior Notes, with a principal amount of $250 million, were issued in December 2012 with interest paid semi-annually in June and December. Our Senior Notes, which are unsecured, unsubordinated obligations, rank equally in right of payment with any existing and future senior unsecured indebtedness.

We may redeem the Senior Notes in whole or in part, at any time at our option at specified redemption prices. In addition, upon the occurrence of certain change of control triggering events, we may be required to repurchase the Senior Notes under specified terms. The Senior Notes also include covenants that limit our ability to incur debt secured by liens on assets or on shares of stock or indebtedness of our subsidiaries; to engage in certain sale and lease-back transactions; and to consolidate, merge or sell all or substantially all of our assets. As of July 31, 2020, we were in compliance with all covenants associated with the Senior Notes.

As of July 31, 2020, our aggregate future principal debt maturities are as follows (in millions):

Fiscal Year	Amount
2023		250
2025		400
2026		750
Thereafter		1,250
Total	$	2,650

We have a commercial paper program (the Program), under which we may issue unsecured commercial paper notes. Amounts available under the Program, as amended in July 2017, may be borrowed, repaid and re-borrowed, with the aggregate face or principal amount of the notes outstanding under the Program at any time not to exceed $1.0 billion. The maturities of the notes can vary, but may not exceed 397 days from the date of issue. The notes are sold under customary terms in the commercial paper market and may be issued at a discount from par or, alternatively, may be sold at par and bear interest at rates dictated by market conditions at the time of their issuance. The proceeds from the issuance of the notes are used for general corporate purposes. As of July 31, 2020 and April 24, 2020, we had commercial paper notes outstanding with aggregate principal amounts of $150 million and $523 million, respectively, weighted-average interest rates of 1.29% and 2.01%, respectively, and maturities primarily less than three months.

During the first quarter of fiscal 2021, we received proceeds of $75 million from the issuance, and made repayments of $76 million for the settlement, of commercial paper notes with original maturities greater than three months.

In connection with the Program, we have a senior unsecured credit agreement with a syndicated group of lenders that expires on December 10, 2021. The credit agreement, as amended in July 2017, provides a $1.0 billion revolving unsecured credit facility, with a $50 million letter of credit sub-facility, that serves as a back-up for the Program. Proceeds from the facility may also be used for general corporate purposes to the extent that the credit facility exceeds the outstanding debt issued under the Program. The credit agreement includes options that allow us to request an increase in the facility of up to an additional $300 million and to extend its maturity date for two additional one-year periods, both subject to certain conditions. As of July 31, 2020 we were in compliance with all associated covenants in this agreement. No amounts were drawn against this facility during any of the periods presented.